Hi there, I am a New Zealander in Berlin and I am trying to locate a bookstore in this city that sells Shadowrun Books. Where should I be looking?
Any help will be greatfully recieved.

Have a look at this page.

I can recommend Serious Games.

I don't know where you'd find sourcebooks for the game, but novels are everywhere. I was passing through the Frankfurt airport a year back, and saw Shadowrun novels that I'd never heard of in English at the airport bookstore.